Glass-drawing apparatus.



H. G. SLINGLUFF.

GLASS DRAWING APPARATUS.

APPLICATION FILED muza. 1908.

1,141,497. Patented June 1, 1915.

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1 OFFICE.

I 'nAaaY. o. 'sLmeLnrnpr-Prr'rsBUaeH, PENNSYLVANIA, Assumes rorI'rrsnU-aon PLATE crass COMPANY, or PITTSBURGH, PENNSYLVANIA, ACORPORATION or PENNSYLVANIA.

I Application iiledlanuary as, 1908. SerialNo.413,002.

To 'all whore it"may conccm'."

Be it known that I, HARRY a citizen of the United States, residing atPittsburgh, in the county ofAlle'ghenyand Drawing'Apparatus of which thefollow ingnif a specification. .7

e invention relate'se to glass drawing apparatus and particularly to theapparatus from which cylinders for the making of window glass are drawn.The invention has forits rincipal objects; the provision of means wereby a cylinder of requisite thick ness may be drawn directly from alarge deep body of glass, andthe provision of apparatus whereby movementor creeping of thecylinder on thesurfacc of the molten mass from which.it is drawn and distortion thereof are avoided. One embodiment of theinvention is illustrated in the accompanying drawing, wherein Figure 1is a transverse section through the end of the drawing tank, the coveror hood being raised to permit reheating of thesurface of the glass inthe tank,

Figure 2 is a section similar to that of Figure 1, but with thesupporting cover ring lowered and the cover removed for draw- Figure 8is' a section through the melting and drawing tanks taken at rightangles to that'of Figures 1 and 2, and shows the cylinder in process ofdrawing, and

Figure 4 is a transverse section through the drawing receptacle. V

Heretofore when the drawing of cylinders has been attempted directlyfrom a melting tank or an extension thereof containing a considerablebody of glass, difliculty has been experienced in securing a cylinder ofsuflicient thickness, due to the too great fluidity ofthe glass at thesurface of: the

mass, which fluidity results from the high temperature which must bemaintained in the main body of the glass. My apparatus is designed toovercome this difliculty by the provision of means for separating aportion of the surface of the glass to bedrawn from the body of theglass beneath, while at the same time maintaining communicatiorf withsuch body of glass. This arrangement permits the temperature of the.surface glass .to fall sufliciently below that of the body of the glassto give a proper viscosity for Specification of Letters Patent.

G. Shiitceijr'r,

. value.

GLASS-DBQJWING APPARATUS.

Patented June 1, 19'] 5.

thickness. .Another difficulty experienced herefioforein drawingdirectly from a large body of glass has been "due to the tendency oftheglass on occasion to creep overthe surface of the mass, and to: drawunequally as a result of the difference in temperature existing atdifferent or'tions of the surface of the glass, such-di erence intemperature tending to cause the glass to blow out unevenly, therebyproducing a cylinder of. .unequal thickness and of small commercial comethis di culty by the provision .of a drawing receptacle which is soconstructed as to maintain the cylinder concentric with My apparatus isdesigned to over-- vtheproduction of a cylinder of requisite the drawingreceptacle regardless of slight unevenness in temperature atdifierent'por tions of the surface of theglass. Referring to theembodiment of the invention as illustrated in the drawing, 1 is thedrawing tank communicating with the melt-- ing tank :2 as'illustrated inFigures 3, 3 is the drawing receptacle, 4 are a pair of'projections uponwhich the drawing receptacle is adapted to rest, 5 is the cover or .hoodwhich is removed when the drawing occurs, 6 is the top stone forcarrying the hood,

ess of drawing (Figure 3). The bottomof the receptacle 3 is providedwith an aperture 9 and the edges of such receptacle are inclincdoutwardly so that when the parts are in the position shown in Figure 3,theoedges of the receptacle approach the top'stone 6 and projectslightly above the surface of the glass.

The foregoing apparatus provides for the separation and consequentcooling of the body of glass lying inside the receptacle, thus reducingthe fluidity of suchlliiaterial in the receptacle, and permitting tliedrawing of a cylinder of greater thickness than has heretofore beenpossible where the body of'glass from which the cylinder was drawn wasin communication with the body of glass at a very high temperature lyingbeneath the point of drawing. 'The arrangement permits of justsuflicient reduction in tem- ,perature of the glass in the receptacle towhich stone is adapted to be mpvsrllu and" give proper drawing, and atthe same time the aperture'in the bottom of. the receptacle Jii permitsof a replenishing oi the glass from the body of glass beneath thereceptacle. Another important function of the construction, is themaintenance of the cylinder throughout the drawing in the position fromwhich the draw was started, which mode of operation insured a c linderof iuiiforin thfckness. In the ,prac ice of the invention with thisapparatus it has been found that the eylinder maintain! itself exactlyeoncentrio with the opening '9- throughout the draw. This function seemsto be due to the fact that the glass over thecenter of the o icnin 9 isverv fluid due to its direct and.

immediate communication with-the hot body of fluid directly beneath andto the fact that the glass in the receptacle outside of the opening 9 ismuch less fluid because of its lower temperature, so that if any portionof the surface of the glass in the receptacle has an unduly hightemperature, which would tend to cause the cylinder to spread in thatdirection to a greater extent than it should as the drawing puogresses,such spreading -wiil be-checked when the edge of the cylinder passesbeyond the edge of the opening 9 because of the increasing thickness orviscosity of the material; and there will be no expansion or him ementoutward of any portion of the base of the cylinder-beyond apredetermined limit. This effect is further augmember with an openingtherethrough lying partially submerged in and surrounded by the glass ofthe tank with the upper edge lying above the surface of the glass, the

opening through the-said drawing member being larger at the top than atthebottom.

-witl1,the edge of the portion of least diameter projecting ben aththe-edge ofthe cylinder being drawn, whereby the glass in the drawingmember is partially segregated from the glass. in the tank beneath thedrawing member. i

In testimony whereof I have hereunto signed my name in the presence ofthe two subscribed witnesses.

HARRY G. SLINGLUFF.

.Vitnesses:

PAUL SYNNESVEDT, J; O. BRADLEY.

